Electrical contact arrangements which withstand pulsed currents and are designed for connection with a polygonal socket are generally well-known. U.S. Pat. No. 5,533,915, for example, discloses a plug connector with two contact arrangements extending in the plug-in direction, the contact arrangements being formed of a cuboid contact pin and a flexible tongue. The flexible tongue is attached to one side of the contact pin, and bends in its arcuate course firstly away from the contact pin, in order subsequently to bend back towards the contact pin. Known flexible tongues are generally made from a resiliently readily deformable steel, for example a spring steel, and has a cross-section which permits sufficiently strong spring force.
On an opposite side from the flexible tongue, the contact pin includes a contact surface for electrical connection with a mating contact, into the socket of which the contact arrangement may be inserted in the plug-in direction.
A contact arrangement configured in this way has the advantage that the mating contact may be of simple construction and in particular does not require a flexible tongue to press down the contact pin, since this is provided by the contact arrangement. The contact arrangement is compactly configured, despite the flexible tongue. The mating contact may be shaped for example as a busbar, in which a polygonal and in particular rectangular socket has been punched. A socket body may be dispensed with, since the socket does not include any further parts; the socket configuration cannot be simplified any further.
Without external forces acting on the contact arrangement, the contact pin inserted into the socket rests against a connection side of the socket and there forms the electrically conductive part of the plug-and-socket connection. The flexible tongue rests against a side wall of the socket and presses the contact pin against the opposing, connection side of the socket. However, the flexible tongue contributes only insignificantly to current conduction, since, compared to the contact pin, it includes a smaller cross-section and a lower specific electrical conductivity than the contact pin, which is made as a rule from a metal with good electrical conductivity.
However, if a mechanical force acts on the contact arrangement, this force may lead to tilting or twisting of the contact pin, in particular around the plug-in direction. This creates risk of the contact pin becoming detached from the mating contact and the plug-and-socket connection between contact arrangement and mating contact being indeterminate. The conductivity of the plug-and-socket connection may diminish drastically.
The forces possibly twisting the plug connector may be caused, for example, by cables hanging from the contact arrangement. Even if no external mechanical forces act on the contact arrangement, the contact pin may tilt if the plug-and-socket connection is arranged in a possibly weak external magnetic field and a pulsed current of a few thousand amperes flows through the contact arrangement at least for a short time, i.e. for example for a period of a few milliseconds. Such pulsed currents may, for example, occur in the region of power electronics circuits in the event of switching processes and generate Lorentz forces, by means of which the contact arrangement may be twisted in the socket.
An indeterminate plug-and-socket connection possibly deteriorating in the event of high currents may lead to operating malfunctions of the power electronics and possibly cause arcing between the contact pin and the mating contact, by which the two contacts may be welded together virtually inseparably. The service life of the contact arrangement or of the mating contact may also be severely reduced by arcing which may arise and by erosion of the contact faces brought about thereby.